1. Field of the Invention
The present invention generally relates to instrumentation for monitoring and recording instrumentation for equipment and well conditions in hydrocarbon wells, water wells, or other well applications. In one aspect, a down hole impact sensing system is disclosed which provides for observing and recording impact loads and hole angles realized by wire line, electric line, coiled tubing, tubing, drill pipe or other tool deployment strings operated “downhole” within a well. In addition, a method of using a downhole impact sensing gyro scope system in well operations is disclosed.
2. Description of the Related Art
Various well operations often require the use of devices which provided an “impact” on a tool string or on a downhole production device. Certain types of downhole tools require the shearing of screws or pins to either set or release a device. For example, a downhole packer or bridge plug run into a well by wireline may require the shearing of screws on the run-in tool in order to set the packer at the desired depth. Shearing of the pins or screws requires that an impact load is delivered to the pins or screws. In other applications, a device may be installed or removed from a production string by use of wireline or coiled tubing. For example, a safety valve or gas lift valve is often installed or removed from the tubing by a wireline-deployed setting or retrieving tool. Retrieval of a safety valve from tubing usually requires the application of a force to the retrieving tool in order to unseat the valve from the tubing.
Typically, a mechanical or hydraulic jarring tool is used to deliver the impact force required for the above operations. However, with known downhole tools, the only indication the operator has on what is occurring down hole is what can be observed on the surface weight indicator which shows the weight on the wireline or coiled tubing string at the surface. However, the information provided by the surface weight indicator is of questionable benefit in determining the events occurring down hole due to many factors but include depth of device from weight indicator, wire stretch, hole deviation, tubing size, friction losses, etc. In general, a surface weight indicator only shows static loads at the surface, as opposed to measuring and recording dynamic loads realized at the depth of the tool. Moreover, any deviations, dog-legs, or other obstructions in the well bore will affect the surface reading.
Information regarding the actual impact realized at the depth of a particular tool can be of assistance to well operations, particularly when difficulties are experience in either setting or retrieving a tool. A record of the impact loads imparted to the tool string may be used to diagnose the difficulty and allow the operator to make changes in tool string design or other operational factors to complete the desired operation. Both the impact load at depth and the hole angle are critical to understanding what the data retrieved means. Surface testing at various angles would allow for a data archive to be held that would be accessed once impact loads and angles were retrieved from the tool. It is at this point that exacting toolstring changes can be made to enable a successful set or retrieve during the next intervention. Well bore deviation is a major factor in friction losses in any deployed toolstring. Wireline toolstring lengths typically range from 15 to 25 ft and as a result friction is unavoidable with hole angle. The greater the hole angle the greater the friction losses both in the toolstring rubbing against the tubing wall and the wireline itself doing the same. The deeper the well the more friction is created.
The present invention is directed to overcoming the problems of the prior art.